AlInAs/GaInAs Metal-Semiconductor-Metal photodiodes with very low dark current

AlInAs/GaInAs Metal-Semiconductor-Metal photodiodes have been fabricated by MBE. The structure incorporates an AlGaInAs graded region to avoid photocarrier trapping and to provide surface passivation. Low dark current and capacitance as well as good responsivity and large bandwidth have been obtained. These combined properties confirm the potential of AlInAs/GaInAs MSM detectors for long-wavelength (1.3-1.55?m) low-noise integrated photoreceiver applications.